Typical components of the above-mentioned type are sensors, such as foil-type platinum temperature sensors, which are generally known and which are used for various purposes. The known platinum temperature sensors are constructed such that a thin platinum wire is glued onto a carrier foil in a meander pattern, said carrier foil consisting e.g. of Kapton. The production of such a sensor is very labour intensive. Further restrictions and drawbacks result from the fact that, even if the foils used have comparatively large dimensions, in the range of a few square centimetres, the wire thicknesses that can be processed permit only low resistance values, in the range of 100 Ohm or less. In addition, small dimensions, e.g. &lt;1 cm.sup.2, with normal resistance values in the range of 100 Ohm cannot be realized at all.
It is known to produce foil temperature sensors with ignoble metals, e.g. nickel, since the metal films can in this case be structured by normal methods after having been coated onto the carrier foil. Such methods include the photoresist technique and chemical etching. The disadvantage which has to be put up with in this connection is that the characteristic of the temperature sensors produced in this way does not comply with the widespread standard DIN IEC. In addition, ignoble metals do not have the high long-term stability of platinum.
Platinum temperature sensors must be subjected to temperature treatments at high temperatures, if possible above 1,000.degree. Celsius, during and/or after the production of the platinum film so as to have a desired stability with regard to their characteristic, which is characterized by their resistance at 0.degree. Celsius, R.sub.o, and the temperature coefficient of the resistor, TK.
However, a foil coated with a metal film cannot be subjected to this treatment, since the carrier foils, which consist of Kapton, metal foils with an insulating coating, glass foils, etc., would be destroyed at these high temperatures. In addition, structuring of a platinum film which is applied to a foil is problematic, since the noble metal platinum can only be etched by very agressive media. Furthermore, foil carriers make it difficult to carry out the necessary trimming process for calibrating the resistors to the desired target values, said trimming process being carried out e.g. by means of exposure to laser radiation.
DE 25 07 731 B2 discloses a measurement resistor consisting of an insulating body as a carrier and of a thin platinum layer as resistance material. This measurement resistor is produced by applying a thin platinum layer to the carrier by cathode sputtering in an oxygen-containing atmosphere, said platinum layer being annealed subsequently. In the case of the method disclosed in this publication, the carrier must resist the high temperatures occurring during the annealing process.
DE 41 13 483 describes a method of producing fine conductor tracks. According to one embodiment, the above-mentioned publication discloses a method including the step of applying a powder of electrically conductive material to sticky areas of an auxiliary surface which correspond to a conductor track pattern. Subsequently, the powder is burnt, whereby conductor tracks are produced which adhere only weakly to the auxiliary or intermediate carrier surface. Following this, the final carrier is applied to the burnt conductor track pattern under pressure, whereupon the carrier is separated from the auxiliary surface, the electrically conductive material sticking to said carrier.
The publication G. Seidel "Gedruckte Schaltungen", Verlag Technik, Berlin, Berliner Union, Stuttgart, 1959, discloses different production modes for printed circuits. In this connection, various printing techniques, electroplating techniques and foil etching processes are described.
DE 39 27 735 A1 discloses a radiation thermometer consisting of a meandrous thin-film resistor applied to a plastic foil. DE 23 02 615 B2 shows a temperature-dependent electric resistor and a method of producing the same. This resistor consists of a meandrous conductor track having a temperature coefficient other than zero, said conductor track being arranged on a thin insulating foil which is arranged on a rod having a cylindrical surface.
In "e&i", 107, volume (1990), No. 5, pages 271 to 275, different components, which are produced by means of a thick-film or a thin-film technique, are explained. In "etz", Vol. 109 (1988), No. 11, pages 502 to 507, thin-film and thick-film technologies used in the field of sensor technology are described.
DE 42 18 938 A1 discloses a method of producing resistor elements comprising the steps of applying a resistor path in the form of a polymerizable electrically conductive paste to a carrier and passing the coated carrier through an infrared oven so as to cause polymerization of said paste. Following this, a plastic core is pressed onto the coated carrier and the carrier is separated from said plastic core, which has the effect that the resistor path resulting from said conductive paste remains in said plastic core. German patent application S 39 021 VIb/32b, date of filing May 5, 1954, published on Oct. 20, 1955, discloses a method of increasing the adherence between metal coatings and glass or ceramics.